/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.solr.search.function;

import org.apache.lucene.index.IndexReader;

import java.io.IOException;
import java.util.Map;

/**
 * <code>ConstValueSource</code> returns a constant for all documents
 */
public class ConstValueSource extends ConstNumberSource {
	final float constant;
	private final double dv;

	public ConstValueSource(float constant) {
		this.constant = constant;
		this.dv = constant;
	}

	@Override
	public String description() {
		return "const(" + constant + ")";
	}

	@Override
	public DocValues getValues(Map context, IndexReader reader)
			throws IOException {
		return new DocValues() {
			@Override
			public float floatVal(int doc) {
				return constant;
			}

			@Override
			public int intVal(int doc) {
				return (int) constant;
			}

			@Override
			public long longVal(int doc) {
				return (long) constant;
			}

			@Override
			public double doubleVal(int doc) {
				return dv;
			}

			@Override
			public String strVal(int doc) {
				return Float.toString(constant);
			}

			@Override
			public String toString(int doc) {
				return description();
			}
		};
	}

	@Override
	public int hashCode() {
		return Float.floatToIntBits(constant) * 31;
	}

	@Override
	public boolean equals(Object o) {
		if (!(o instanceof ConstValueSource))
			return false;
		ConstValueSource other = (ConstValueSource) o;
		return this.constant == other.constant;
	}

	@Override
	public int getInt() {
		return (int) constant;
	}

	@Override
	public long getLong() {
		return (long) constant;
	}

	@Override
	public float getFloat() {
		return constant;
	}

	@Override
	public double getDouble() {
		return dv;
	}

	@Override
	public Number getNumber() {
		return constant;
	}
}
